You can filter the cloudflare data for “likely automated” and “likely human” and that gives you ~6% Linux in the last 4 weeks. Cloudflares main business is bot and DDOS protection on a global scale, so their numbers will be the best you can get:

I would think most of it, since when you filter for other regions (Europe, Asia, etc), you don’t get such a strong trend. So if it is mostly driven by the US, I would exclude single users to be the cause. I don’t think there is any reason the user market would be this different there from other parts of the world.